Crucible for slug casting machines and method of making same



Dec. 6, 1938. .c E MURRAY 2,139,511

CRUCIBLE FOR SLUG CASTING MACHINES AND METHOD OF MAKING SAME Filed July 12, 1957 9 IIII,IIIIIIIIIIIIII'IIIIIl FIG. 3

FIG. 5

INVENTOR.

C.E.MUR

ATTORNEY.

Patented Dec. 6, 1938 PATENT OFFICE oaUoIBLEFon spUG CASTING MACHINES AND METHOD OF MAKING SAME Clay Murray, Davenport, Iowa, assignor to Linograph Corporation, Davenport, Iowa, a cor- 'poration of Delaware "App-natio July 12, 1937, Serial 153,190

2 Claims.

The present invention relates to improvements in typographical machines of the well-known class shown and described generally in TIT. S. Patent No. 436,532 granted September 16, 1890, wherein character bearing matrices stored in a magazine are delivered therefrom under the control of a keyboard and assembled in lines from which type bars or slugs are cast, after which the matrix lines are returned to their appropriate channels in the magazine by distributing mechanism, and relates more particularly to crucibles forming a part of such a machine. It has been found that it is impossible to successfully use cast metal in the making of these crucibles, the reasons being various. One reason is that cast iron is more or less subject to porosity with the result that the molten type-metal passes through the wall of the crucible. Another reason is that the crucible is subject to uneven heating which results in uneven expansion and cracking of the crucible, with the result that a new one must be supplied, since cast iron cannot be successfully welded so as to retain type-metal. Another objection to cast iron crucibles is that, when typemetal is permitted to solidify therein, it clings to the rough surface of the cast iron and then, when the metal is heated to remelt it, it expands first in the bottom of the crucible, often resulting in the well being pulled away from the bottom of the pot. This does not happen with the steel crucibles, the tenacity of which is greater than the adhesiveness of the type-metal with respect to the'well. When crucibles are made from cast iron, it is impossible to accurately control the size, shape, and surface condition of the interior of the throat. This drawback is not present when the crucibles are made from steel plate. Cast iron crucibles often have surface projections in the throat to which the dross and metal adheres and upon which serious obstructions are built up. This objection is absent in crucibles built in accordance with my invention. Various other objections, also, have been found and it Was with the purpose of overcoming these objections that I began experimenting with rolled steel in an effort to find a material not subject to the faults of cast iron. This material is entirely impervious to the passage of molten type-metal and, if a leak develops between two parts of the assembled structure, it is easy to fuse the parts at the point wherethe leak occurs and thus eliminate the leak. Sometimes it is more desirable to fuse on a small quantity of steel to close the opening, similarly as solder would be applied to tin or copper. By utilizing this method of construction, the percentage of loss has been reduced from one which was quite high 110 .One Which is nearly negligible.

Stated briefly, the objects of this invention are v toproduce a crucible in which the manufacturing loss is small; to provide a crucible in which the number of leaks which develop in the crucible, during use, will be reduced to a minimum; to provide a crucible which can be easily repaired in event a leak should at any time develop; to provide a more eflicient structure of the character indicated; and such further objects, advantages, and capabilities as will hereafter appear and as are inherent in the cnstruction disclosed herein. My invention further resides in the combination, construction, and method of assembly illustrated in the accompanying drawing and, while I have disclosed therein what is now regarded as the preferred embodiment of this invention, I desire the same to be understood as illustrative only and not to be interpreted in a limiting sense.

In the drawing annexed hereto and forming a part hereof,

Fig. 1 represents an elevation of a structure embodying my present invention;

Fig. 2 represents a longitudinal section of the structure shown in Fig. 1;

Fig. 3 represents a transverse section of the throat taken substantially along the plane indicated by the line 3-3, Fig. 2;

Fig. 4 represents a fragmentary bottom plan of the structure shown in Fig. 1;

Fig. 5 represents a fragmentary top plan of this structure;

Fig. 6 represents an elevation of the well, shown in section in Fig. 2.

Referring more in detail to the annexed drawing, the. pot is designated by the numeral I, the well by the numeral 2, and the throat by the numeral 3. In the making of the elements I and 3, suitable pieces are cut from sheet steel and then shaped to the desired form. To make the well 2, a suitable length is cut from a piece of steel pipe and then a notch 4 is formed in one end to permit the molten metal to flow from the well into the throat. The plate which is cut out to form the pot I has a notch cut in one corner, as is apparent from Figs. 2 and 5, for the reception of the throat 3. A disc 5 is out out to fit against the end of the approximately cylindrical part of pot I, and a notch is cut therein to receive the well and throat, as is apparent from Figs. 1 and 2.

The lower plate 6 of the throat 3 is longer than the upper plate 1, the excess extending out, as indicated at 8, to form the bottom of the well 2. Strips 9 form ,the sides of the throat and are ex tended beyond the top plate I, as indicated at I0, to close up the notches 4 in the bottom end of the well 2. More or less triangular pieces II are fitted in between the bottom 5, the throat plate 6, and the wall of the pot I. All the metal parts, Where they contact, are welded so as to produce astructure completely impervious to molten typemetal.

In rolling the metal sheet to produce the approximately cylindrical wall of the pot l, a portion I2 thereof is left flat and contacts the upper surface of the throat 3 in an approximately straight line, as is apparent in Fig. 5. The two ends of the pot wall abut, as indicated at 13, and are welded, just as all other abutting surfaces are. As indicated at M in Figs. 1 and 5, a portion of the wall of the notch in the corner of the plate from which the pot is formed is somewhat curved in order to make it abut against the plate I so that it can be welded thereto.

It is of course understood that the specific description of structure and method set forth above may be departed from without departing from the spirit of my invention as set forth in this specification and the appended claims.

Having now described my invention, I claim:

1. A crucible of the type described comprising a pot, a well, and a throat, the pot being formed from sheet metal blanked and shaped into desired form, the well being formed from steel tubing cut to the desired form, and the throat being fabricated from pieces of sheet steel cut tothe desired shape and secured together in leak-proof relation, the parts being fused at their points of contact to produce joints impervious to molten typemetal.

2. In the art of making crucibles for type casting, those steps which comprise cutting a piece of steel tubing into the necessary form for a well, cutting a blank from a steel plate of a size and form to be shaped into a pot, shaping the pot, cutting strips of steel into shapes to be assembled and constitute a throat, assembling and welding the throat, cutting out a piece of sheet steel to constitute the bottom of the pot, assembling and welding the throat and well, assembling the pot bottom with the throat-well structure and welding them together, assembling the pot with the previously assembled structure and welding the parts together in leak-proof relation.

CLAY E. MURRAY. 

